Conventionally, there has been widely known a sliding door opening and closing device that operates to open or close a passenger sliding door provided in a side portion of a vehicle using a drive source such as a motor. The sliding door opening and closing device mentioned above allows a sliding door to start an opening and closing operation by detecting a stopped state of the vehicle on the basis of information such as the speed of a vehicle, or the shift lever position of the transmission for a safety reason. When pinching of an obstacle is detected during a movement of the sliding door, control for stopping the sliding door or actuating the sliding door in a reverse direction is executed.
When the vehicle is changed to a moving state from a stopped state during the opening and closing operation of the sliding door, the acceleration generated at the start of the movement is applied to the sliding door, and an inertia force applied to the sliding door is erroneously detected as pinching of an obstacle so that the sliding door is stopped or actuated in the reverse direction. Accordingly, there has been proposed a sliding door opening and closing device which suppresses such erroneous detections of pinching as mentioned above by increasing a determination threshold value serving as a determination reference for detecting pinching when the vehicle stopped state is cancelled during the opening and closing operation of the sliding door (refer to Patent Document 1). In the sliding door opening and closing device in accordance with this proposal, it is determined that the vehicle stopped state is cancelled when the shift lever of the transmission is shifted to a position other than a parking position, or when the speed of the vehicle becomes higher than a certain value.
In the meantime, even if the shift lever of the transmission is shifted to a position other than the parking position, there could be a case where the vehicle stopped state carries over if the foot brake is stepped on. If the determination threshold value for detecting pinching is increased in the vehicle stopped state, there may be a case where the pinching detection is not executed even if an obstacle is pinched.
Further, when the vehicle starts, the acceleration at the starting could be applied to the sliding door before the speed of the vehicle is detected, depending on the detecting method of the vehicle speed. In such a case, inertia force is applied to the sliding door before the determination threshold value is increased, and the pinching may be erroneously detected.
Patent Document 1: Japanese Patent No. 3511347